Cross band carriers

ABSTRACT

Methods, systems, and devices for wireless communication are described. Downlink carriers in the millimeter wave spectrum may be paired with one or more carriers in a lower frequency spectrum, such as one or more uplink carriers in a sub-6 GHz band.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationSer. No. 62/562,926 entitled CROSS BAND CARRIERS, filed on Sep. 25,2017, which is incorporated by reference herein in its entirety.

BACKGROUND

The following relates generally to wireless communication, and morespecifically to uplink and downlink cross-band carriers.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include code division multiple access (CDMA)systems, time division multiple access (TDMA) systems, frequencydivision multiple access (FDMA) systems, and orthogonal frequencydivision multiple access (OFDMA) systems. A wireless multiple-accesscommunications system may include a number of base stations, eachsimultaneously supporting communication for multiple communicationdevices. Communication devices that are user-specific are referred to asuser equipment (UE).

In order to provide more and better wireless services, use of spectrumin higher frequencies is being explored. For example, use of portions ofthe millimeter wave (mmW) spectrum (which extends from 30 GHz to 300GHz), is being considered for telecommunications applications.

Use of non-mmW spectrum may be restricted due to government regulationor other agreements. For example, different portions of theelectromagnetic spectrum may be subject to license by a governmentalentity. Spectrum licenses may be exclusive, or the spectrum may beshared. Additionally, some aspects of telecommunications devices may besubject to safety regulations. For example, some regulations placerestrictions on the amount or other characteristics of transmissionpower.

SUMMARY

Methods, systems, and devices for wireless communication are described.The techniques allow for different configurations of uplink and downlinkcarriers; for example, in a system where downlink signals are in the mmWportion of the electromagnetic spectrum while uplink signals may be innon-mmW bands.

In general, in one aspect, a method of wireless communication performedby a user equipment (UE) in communication with a base station comprisesreceiving information indicative of a plurality of candidate uplinkcomponent carriers in the non-mmW spectrum, each of the plurality ofcandidate uplink component carriers available to be associated with aparticular downlink component carrier in the mmW spectrum. In responseto receiving the information indicative of the plurality of candidateuplink component carriers the UE can select at least a primary uplinkcomponent carrier from the plurality of candidate uplink componentcarriers. The UE can transmit a signal to the base station using theprimary uplink component carrier.

The information indicative of a plurality of candidate uplink componentcarriers in the non-mmW spectrum may include at least frequencyinformation (such as the center frequency of the candidate uplinkcomponent carrier), as well as one or more random access channel (RACH)parameters for each of the candidate uplink component carriers.

The UE can select at least a primary uplink component carrier from theplurality of candidate uplink component carriers by determining that aset S of candidate uplink component carriers are supported by the UE,where there are T candidate uplink component carriers. If all candidatecarriers are supported, then S=T. If S>1, the primary uplink componentcarrier can be selected from the S supported candidate uplink componentcarriers based on one or more uplink communication parameters. Thecommunication parameters include UE compatibility with each of thecandidate uplink component carriers, a current load level of each of theS supported candidate uplink component carriers, an expected load levelof each of the S supported candidate uplink component carriers, and anincumbent priority for each of the S supported candidate uplinkcomponent carriers. The UE can select at least one secondary uplinkcomponent carrier from the candidate uplink component carriers. In someimplementations, the UE receives a configuration of one or moresecondary uplink component carriers from the base station.

The UE transmits a capability report to the base station, where thecapability report can include UE uplink carrier capability information.The UE may transmit control signaling and data to the base station usingthe primary uplink component carrier and transmit data to the basestation using the one or more secondary uplink component carriers,although in some implementations the UE transmits some controlinformation using the secondary uplink component carriers in addition todata. The control signaling can include downlink hybrid automatic repeatrequest (HARQ) information, channel state information (CSI), schedulingrequest (SR) information, and random access channel (RACH) information.

In general, a method of wireless communication performed by a basestation in communication with a user equipment (UE) includestransmitting information indicative of a plurality of candidate non-mmWuplink component carriers to be paired with a particular downlink mmWcomponent carrier. The base station receives an indication of apreferred uplink component carrier of the plurality of candidate uplinkcomponent carrier from the UE and selects the preferred uplink componentcarrier or a different uplink component carrier as an initial primaryuplink component carrier for the UE, and configures the UE with theinitial primary uplink component carrier.

The base station may select the different uplink component carrier as aninitial primary uplink component carrier rather than the preferreduplink component carrier based on system parameters such as relativeloading of the different uplink component carrier and the preferreduplink component carrier. For example, if loading of the preferredprimary uplink component carrier is more than a threshold amount aboveloading of the different primary uplink component carrier, then the basestation may select the different primary uplink component carrier forimproved load balancing.

Aspects generally include methods, apparatus, systems, computer programproducts, and processing systems, as substantially described herein withreference to and as illustrated by the accompanying drawings.

Other aspects, features, and embodiments of the present invention willbecome apparent to those of ordinary skill in the art, upon reviewingthe following description of specific, exemplary aspects of the presentinvention in conjunction with the accompanying figures. While featuresof the present disclosure may be discussed relative to certain aspectsand figures below, all embodiments of the present disclosure can includeone or more of the advantageous features discussed herein. In otherwords, while one or more aspects may be discussed as having certainadvantageous features, one or more of such features may also be used inaccordance with the various aspects of the disclosure discussed herein.In similar fashion, while exemplary aspects may be discussed below asdevice, system, or method aspects it should be understood that suchexemplary aspects can be implemented in various devices, systems, andmethods.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a wireless communications systemaccording to some implementations;

FIG. 2A illustrates an example of a wireless device according to someimplementations;

FIG. 2B illustrates an example of a base station according to someimplementations;

FIG. 3 illustrates an example method for a UE according to someimplementations;

FIG. 4 illustrates an example method for a UE according to someimplementations;

FIG. 5 illustrates an example method for a base station according tosome implementations; and

FIG. 6 illustrates an example method for a base station according tosome implementations.

DETAILED DESCRIPTION

While the expansion of telecommunications into new frequency regimes canprovide a number of benefits, new frequency bands such as thoseassociated with the millimeter wave portion of the electromagneticspectrum present new challenges for devices and protocols.

One issue that may arise with new spectrum is the intersection ofregulation with technology. For example, in the United States, somekinds of wireless devices need to comply with Maximum PermissibleExposure (MPE) restrictions. Depending on their use and configuration,some UEs may ensure compliance with MPE restrictions by using non-mmWcarriers in the uplink (transmissions from the UE to the network entity)and using the mmW band exclusively on the downlink (transmissions from anetwork entity such as a base station to the UE). Other UEs may bedesigned to selectively use either mmW or non-mmW transmissions on theuplink. Devices that are not routinely proximate to a user's body, suchas some Customer Premises Equipment (CPE), may be designed to use mmWspectrum for both uplink and downlink communications.

Systems and techniques herein use cross-band pairing of downlink mmWcarriers with one or more non-mmW uplink carriers. Uplink carrierfrequencies that are less than ten GHz can be used; in particular, thesub-6 GHz bands can mitigate regulatory concerns and are compatible withmany UE designs. Examples of sub-6 GHz bands are 3.4-3.8 GHz, 3.8-4.2GHz, and 4.4-4.9 GHz. Although using the sub-6 GHz bands on the uplinkcan be beneficial, some aspects of using the sub-6 GHz bands can bechallenging. For example, although currently 5G NR (New Radio) supportsup to 100 MHz carrier widths in the sub-6 GHz bands, a contiguousallotment may not be available since the sub-6 GHz band may befragmented (the spectrum available for use may not be in a singlecontiguous band, but may be made up of smaller portions of spectrum).There are a number of reasons the available spectrum may be fragmented.

For a licensed band, a licensee may not have access to a contiguousallocation in the spectrum—for example, the licensee may have oneallotment in one portion of the band and another allotment in adifferent portion of the band that is not contiguous with the firstportion (or is in a different band). For an unlicensed portion of thenon-mmW spectrum, medium sharing may result in a node with access to anon-contiguous uplink spectrum. For a shared portion of the non-mmWspectrum, protection of the existing incumbent (a prior user such as agovernmental entity who has priority of shared spectrum) may result in anode with access to non-contiguous uplink spectrum.

In the current version of the 3GPP (3rd Generation Partnership Project)specification, a UE cannot be configured with more uplink componentcarriers than downlink component carriers. In order to provide efficientand compliant communication when using different spectrum on the uplinkand on the downlink, systems and techniques for cross-band pairingdescribed herein allow for pairing a non-mmW primary uplink componentcarrier and optionally one or more secondary uplink component carrierswith a particular mmW downlink carrier. Herein, the phrase “componentcarrier” refers to a single carrier or one of a plurality of carriersfor a carrier aggregation implementation, while cross-band pairingrefers to association of one or more uplink carriers in non-mmW bands(e.g., one or more of the sub-6 GHz bands) paired with a single downlinkcarrier in a different spectrum band (e.g., the mmW band).

Some aspects that affect cross-band pairing are spectrum availability,spectrum use characteristics, and UE capability. As explained above,different telecommunications service providers may have limitedavailable spectrum due to fragmentation. Even when a service provider isable to access particular portions of the spectrum, use characteristicssuch as loading may make some portions more or less desirable for aparticular communication. Additionally, different UEs may also havedifferent capabilities for supporting communications in differentspectral regimes. For example, a service provider may have a firstspectrum allotment in the sub-6 GHz spectrum with a first centerfrequency and a second spectrum allotment with a second higher centerfrequency, but a UE may only be able to support communications in thefirst spectrum allotment having the lower center frequency.

In some implementations, the cross-band pairing process may be mostlymanaged by a base station, while in others the UE may do some or all ofthe management. Examples of these implementations are described belowwith reference to the figures.

Systems and techniques for cross-band pairing are described with respectto example system 100 of FIG. 1. Wireless communications system 100includes base stations 105, user devices (UEs) 115 (including UE 115 aand UE 115 b), CPE 116, and a core network 130. A UE 115 may also bereferred to as a mobile station, a subscriber station, a remote unit, awireless device, an access terminal (AT), a handset, a user agent, aclient, or like terminology. A UE 115 may also be a cellular phone, awireless modem, a handheld device, a personal computer, a tablet, apersonal electronic device, a machine type communication (MTC) device,etc. In some examples, the wireless communications system 100 may be aLong Term Evolution (LTE)/LTE-Advanced (LTE-A) network, a 5G network, ora network that provides services with a combination of protocols.

In the example of FIG. 1, UE 115 a is configured to use communicate withbase station 105. Each mmW downlink component carrier is paired with atleast a primary uplink component carrier one or more uplink carriers. UE115 a is configured to use exclusively non-mmW carriers on the uplink.By contrast, UE 115 b is configured to selectively use either non-mmWcarriers in the uplink or mmW carriers in the uplink paired withreceived signals on mmW downlink carriers. CPE 116 is configured to pairuplink mmW signals with downlink mmW signals.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., S1, etc.). Base stations105 may communicate with one another over backhaul links 134 (e.g., X2,etc.) either directly or indirectly (e.g., through core network 130).Base stations 105 may perform radio configuration and scheduling forcommunication with UE 115 a and UE 115 b and CPE 116, or may operateunder the control of a base station controller (not shown). In someexamples, base stations 105 may be macro cells, small cells, hot spots,or the like. Base stations 105 may also be referred to as eNodeBs (eNBs)or gNodeBs (gNBs) 105.

FIG. 2A shows a simplified drawing of an example UE 115, referred to asUE 215. UE 215 includes antenna circuitry 230 and transceiver circuitry225. Transceiver circuitry 225 includes receive circuitry with one ormore receive (Rx) chains 227 having RF components such as amplifiers,analog to digital converters, mixers, oscillators, filters, etc. forprocessing received downlink signals, as well as transmit circuitry withone or more transmit (TX) chains 228 including RF components to generatesignals to transmit on the uplink. Characteristics of the transceivercircuitry 225 for UE 215 can affect its ability to support particularuplink or downlink component carriers. UE 215 may support the entiretyof available uplink non-mmW spectrum, or may support only part of thespectrum. For example, a particular UE design may have transmit chain(s)228 that can support uplink signals in a first sub-6 GHz band but not asecond sub-6 GHz band, or may support a portion but not all of aparticular band. Similarly, the receive chain(s) 227 may support theentire width of the downlink mmW spectrum, or a portion.

UE 215 includes processor circuitry 220 and memory circuitry 240.Processor circuitry 220 and memory circuitry 240 are shown as discreteblocks, but may be implemented in a number of ways; for example,processor circuitry may be implemented in one or more dedicated areas ofa chip or in different chips. Similarly memory circuitry 240 may beimplemented as a main memory with or without the addition of otherportions of memory circuitry on the same or different chips. Forcommunications in the mmW spectrum, antenna circuitry 230 works withprocessor circuitry 220 and memory circuitry 240 to implementbeam-related techniques such as beam scanning and management forcommunication with one or more base stations such as base station 105.Note that herein “processor circuitry” and “processor” are used to referto structure.

UE 215 may store capability information as part of stored data andinstructions 245 in memory circuitry 240. UE capability information mayindicate support for communication using particular frequencies. Inoperation, UE 215 executes the techniques described below to implementcross-band pairing. For example, UE 215 may receive signals includinginformation for a plurality of candidate uplink component carriers usingantenna circuitry 230 and receive circuitry including receive chain(s)227 of transceiver circuitry 225, described more fully below and inreference to FIG. 3. The information may be stored in memory circuitry240 to be accessed and processed using processor circuitry 220. Forexample, processor circuitry 220 may select a preferred primary uplinkcomponent carrier and optionally one or more preferred secondary uplinkcomponent carriers using the techniques outlined below. Processorcircuitry 220 may generate a message including a capability report, andmay at times generate messaging indicating preference for different(updated) primary and/or secondary uplink component carriers. In otherimplementations, described more fully below and in reference to FIG. 4,UE 215 may receive signals including an initial configured primaryuplink component carrier using antenna circuitry 230 and receivecircuitry including receive chain(s) 227 of transceiver circuitry 225,while processor circuitry 220 generates a message including thecapability report, as well as the other aspects described below.

FIG. 2B shows a simplified drawing of an example base station 205. Basestation 205 may include processor circuitry 226, memory circuitry 249,antenna circuitry 235, and transceiver circuitry 229. As noted above,base station 205 can participate in communications with UEs such as UE115 a and UE 115 b on a number of component carriers using associatedcells. Here, the term “cell” being used to denote structure such as dataand instructions 247 stored on memory circuitry 249 to generate signalinformation upon execution by processor circuitry 226, and transceivercircuitry 229 and antenna circuitry 235 transmitting the signals usingthe particular component carrier associated with the cell. In operation,base station 205 executes the techniques described below to implementcross-band pairing. For example, base station 205 may transmitinformation indicative of a plurality of candidate uplink componentcarriers using transmit circuitry of transceiver circuitry 229 andantenna circuitry 235, as described below and in FIG. 5. Base station205 receives transmission from UEs such as UE 115 on a selected primaryuplink component carrier (and/or an indication of a preference for aprimary uplink component carrier), as well as a capability report foreach UE, which can be stored in memory circuitry 249 and processed byprocessor circuitry 226 to determine uplink component carriers to bepaired with a particular downlink carrier. Base station 205 and the UEcommunicate using the downlink component carrier and the one or morepaired uplink component carriers. Base station 205 may optionallyreconfigure the UE with a different (updated) primary uplink componentcarrier (and/or different secondary uplink component carrier(s)) duringa connection. For example, base station 205 may improve load balancingamong more than one communicating UEs by changing the component carriersfor one or more connected UEs and/or by its configuration of componentcarriers to UEs as part of connection. In another implementation, asdescribed below and in FIG. 6, base station 205 may transmit informationof initial configured primary uplink component carrier using antennacircuitry 235 and transceiver circuitry 229, and enter a connectedstation using the initial configured primary uplink component carrier.Upon receiving a capability report from the UE, the base station mayoptionally configure UE with one or more secondary component carriersand may at some point optionally reconfigure the UE with a differentprimary uplink component carrier.

FIG. 3 shows a flow diagram for a method 300 that may be used for a UE115 to communicate with a base station 105 using a connection thatincludes one or more uplink sub-mmW carriers paired with a particulardownlink mmW component carrier. Method 300 is managed at least partiallyby UE 115, so that it can autonomously select at least a primary uplinkcomponent carrier from a plurality of candidate uplink componentcarriers.

At 310, UE 115 receives information indicative of a plurality ofcandidate uplink component carriers from a base station 105. Forexample, in establishing a connection, a particular gNB advertises morethan one sub-6 GHz uplink component carrier to pair with a particularmmW downlink component carrier. The received information includesidentification of each of the candidate uplink component carriers (e.g.,frequency information such as its center frequency). In someimplementations, random access channel (RACH) parameters for eachcandidate uplink component carrier are also included in theadvertisement of the candidate uplink component carriers. If basestation 105 is going to use carrier aggregation on the downlink (eitherwith multiple cells of one base station or cells from more than one basestation), UE 115 may receive information indicative of a plurality ofcandidate uplink component carriers for some or all of the downlinkcomponent carriers, although the information can be provided atdifferent times and need not come from a single base station 105.

At 320, in response to receiving the information, UE 115 selects atleast a primary uplink component carrier that complies with thecapabilities of UE 115 and optionally communicates an indication of thepreferred primary uplink component carrier to base station 105. Forexample, if UE 115 supports some but not all uplink center frequencies,UE 115 will select a primary uplink component carrier from a group of Ssupported carriers of the total T candidate uplink component carriers.If UE 115 supports more than one of the candidate uplink carriers, theUE may choose a primary uplink component carrier based on some aspectthat makes one or more component carriers preferable compared to othercandidate uplink component carriers, or it may choose from among thesupported candidate uplink component carriers at random or in some otherway that is not based on the characteristics of the candidate uplinkcomponent carriers (e.g., random selection).

For example, in some embodiments UE 115 selects the primary uplinkcomponent carrier based on one or more uplink communication parametersthat can make a particular candidate uplink component carrier preferableto other candidate uplink component carriers. The uplink communicationparameters include compatibility with the UE 115, relativecurrent/expected load levels for the candidate uplink componentcarriers, incumbent access to the candidate uplink component carriers,or other parameters.

One parameter that may be used to select at least a primary uplinkcomponent carrier is the compatibility of the UE with the candidateuplink component carriers. Some candidate uplink component carriers maybe more compatible with the particular configuration of UE 115. Forexample, the UE may be capable of supporting both first and secondcandidate uplink component carriers, but its RF design may be bettersuited to processing the center frequency of the first candidate uplinkcomponent carrier. Another parameter that may be used to select at leasta primary uplink component carrier may be a consideration of the currentand/or expected load of the candidate uplink component carriers. Forexample, UE 115 may use media sensing to determine carrier loading. IfUE 115 observes a lower load on the first candidate uplink componentcarrier compared to the second candidate uplink component carrier, itmay select the first candidate uplink carrier. Another parameter thatmay be used to select at least a primary uplink component carrier may beincumbent access to the different carriers. For example, if an incumbenthas priority for the first candidate uplink component carrier but notthe second candidate uplink component carrier, UE 115 may select thesecond candidate uplink component carrier.

At 330, UE 115 communicates with base station 105 by transmitting asignal to base station 105; for example, using the selected primaryuplink component carrier. During communication with base station 105, UE115 sends a UE capability report including UE uplink carrier capabilityinformation using the initial selected primary uplink component carrier.Base station 105 may use the UE capability report to configure one ormore secondary uplink component carriers, or to reconfigure the primaryuplink component carrier, as described in more detail below in referenceto FIG. 4.

At 340, UE 115 may select or be configured with one or more secondaryuplink component carriers paired to the downlink mmW carrier. If UE 115selects secondary uplink component carrier(s) paired to the downlink mmWcarrier, it can notify base station 105 as part of its signaling, or insome implementations it may be able to notify base station 105implicitly by communicating with base station 105 using the secondaryuplink component carrier(s).

At 350, UE 115 and base station 105 communicate using the downlink mmWcomponent carrier paired with the primary uplink component carrier andoptionally one or more secondary uplink component carriers. In someimplementations, UE 115 may transmit control signaling on the primaryuplink component carrier and use both primary and secondary componentcarriers for data transmission. Control signaling that is transmitted onthe primary uplink component carrier can include downlink HARQ (hybridautomatic repeat request) information, CSI (channel state information),scheduling request (SR) information, and RACH signaling.

At 360, at a later time, UE 115 may optionally select and/or bereconfigured with a different primary uplink component carrier. Forexample, UE 115 may select a different primary uplink component carrierbased on changes in communication parameters (such as a changing inloading for different uplink component carriers). UE 115 may indicate apreferred primary uplink component carrier to base station 105, and maybe reconfigured to that preferred primary uplink component carrier ifappropriate. Base station 105 may reconfigure UE 115 based oncommunication conditions (e.g., load balancing among carriers).

FIG. 4 shows a flow diagram for a method 400 that may be used for a UE115 to communicate with a base station 105 using a connection thatincludes one or more uplink component carriers in a non-mmW band such asthe sub-6 GHz bands paired with a particular downlink mmW componentcarrier. Method 400 is an implementation that is managed at leastpartially by base station 105. For example, a gNB identifies at least aninitial configured primary uplink component carrier from its allottedspectrum, and advertises a single “paired” uplink component carrier andits corresponding RACH parameters in a transmission to a UE.

At 410, UE 115 receives information indicative of an initial configurednon-mmW primary uplink component carrier from a base station 105 for apairing with a particular downlink mmW component carrier. The receivedinformation includes identification of the initial configured primaryuplink component carrier such as its center frequency and/or otherfrequency information, as well as RACH parameters for the primary uplinkcomponent carrier.

At 420, in response to receiving the information, UE 115 enters aconnected state using the initial configured primary uplink componentcarrier. At 430, UE 115 sends a UE capability report including UE uplinkcarrier capability information to base station 105 using the initialconfigured primary uplink component carrier. At 440, UE 115 may selector be configured with one or more secondary uplink component carrierspaired to the downlink mmW carrier. For example, base station 105 mayaccess the received UE uplink carrier capability information anddetermine that UE 115 can support more than one uplink componentcarrier, and in response configure at least one secondary uplinkcomponent carrier for UE 115 to use on the uplink.

At 450, UE 115 and base station 105 communicate using the downlink mmWcomponent carrier paired with the primary uplink component carrier andoptionally one or more secondary uplink component carriers. In someimplementations, UE 115 may transmit control signaling on the primaryuplink component carrier and use both primary and secondary componentcarriers for data transmission. Control signaling that is transmitted onthe primary uplink component carrier can include downlink HARQ (hybridautomatic repeat request) information, CSI (channel state information),scheduling request (SR) information, and RACH signaling.

At 460, UE 115 may select and/or be configured with a different primaryuplink component carrier at a later time. For example, UE 115 mayindicate a preference for a different primary uplink component carrier(e.g., based on changes in communication parameters such as a changingin loading for different uplink component carriers). UE 115 may indicatea preferred primary uplink component carrier to base station 105, andmay be reconfigured to that preferred primary uplink component carrierif appropriate. Base station 105 may reconfigure UE 115 based oncommunication conditions (e.g., load balancing among carriers).

FIG. 5 shows a flow diagram for a method 500 that may be used for a basestation 105 to communicate with a UE 115 using a connection thatincludes one or more uplink sub-mmW carriers paired with a particulardownlink mmW component carrier. Method 500 is managed at least partiallyby UE 115, so that it can autonomously select at least a primary uplinkcomponent carrier from a plurality of candidate uplink componentcarriers.

At 510, base station 105 transmits information indicative of a pluralityof non-mmW candidate uplink component carriers to UE 115. Base station105 is associated with a particular telecommunications service provider,and can select candidate uplink component carriers from one or more of(1) licensed spectrum allotment(s), (2) shared spectrum portion(s), and(3) unlicensed spectrum portions. For example, in establishing aconnection, a particular gNB determines a plurality of sub-6 GHz uplinkcomponent carriers and advertises the candidate uplink componentcarriers to UE 115 to pair with a particular mmW downlink componentcarrier.

At 520, base station 105 receives a transmission from UE 115 on aselected preferred primary uplink component carrier of the plurality ofcandidate uplink component carriers, and may receive an indication ofthe preferred primary uplink component carrier. During communicationwith UE 115, base station 105 receives a UE capability report includingUE uplink carrier capability information. Base station 105 may configureUE 115 with the preferred primary uplink component carrier or in somecases a different primary uplink component carrier. For example, basestation 105 may configure UE 115 with a different primary uplinkcomponent carrier if the different primary uplink component carrier issupported by UE 115 but improves load balancing. Base station 105 maychoose the different primary component carrier based on relative loadingof the different uplink component carrier and the preferred uplinkcomponent carrier. Base station 105 may use the UE capability report toconfigure one or more secondary uplink component carriers, or toreconfigure the primary uplink component carrier.

At 530, base station 105 and UE 115 communicate using the downlink mmWcomponent carrier paired with the primary uplink component carrier andoptionally one or more secondary uplink component carriers. In someimplementations, base station 105 may receive control signaling on theprimary uplink component carrier and data transmissions on both primaryand secondary component carriers for data transmission from UE 115.

At 540, at a later time, UE 115 may optionally be reconfigured with adifferent primary uplink component carrier. For example, UE 115 mayprefer a different primary uplink component carrier based on changes incommunication parameters (such as a changing in loading for differentuplink component carriers or other aspects such as a received signalstrength indicator (RSSI)). UE 115 may indicate a preferred primaryuplink component carrier to base station 105, and may be reconfigured tothat preferred primary uplink component carrier if appropriate. Basestation 105 may reconfigure UE 115 based on communication conditions(e.g., load balancing among carriers).

FIG. 6 shows a flow diagram for a method 600 that may be used for a basestation 105 to communicate with a UE 115 using a connection thatincludes one or more uplink component carriers in a non-mmW band such asthe sub-6 GHz bands paired with a particular downlink mmW componentcarrier. Method 600 is an implementation that is managed at leastpartially by base station 105. For example, a gNB identifies at least aninitial configured primary uplink component carrier from availablespectrum, and advertises a single “paired” uplink component carrier andits corresponding RACH parameters in a transmission to a UE.

At 610, base station 105 transmits information indicative of an initialconfigured non-mmW primary uplink component carrier to UE 115 for apairing with a particular downlink mmW component carrier. Thetransmitted information includes identification of the initialconfigured primary uplink component carrier such as its center frequencyand/or other frequency information, as well as RACH parameters for theprimary uplink component carrier.

At 620, in response to receiving the information, base station 105 andUE 115 enter a connected state using the initial configured primaryuplink component carrier. At 630, base station 105 receives a UEcapability report including UE uplink carrier capability information tobase station 105 using the initial configured primary uplink componentcarrier. At 640, base station 105 may optionally configure UE 115 withone or more secondary uplink component carriers paired to the downlinkmmW carrier.

At 650, UE 115 and base station 105 communicate using the downlink mmWcomponent carrier paired with the primary uplink component carrier andoptionally one or more secondary uplink component carriers. As notedabove, UE 115 may transmit control signaling on the primary uplinkcomponent carrier and use both primary and secondary component carriersfor data transmission. Control signaling that is transmitted on theprimary uplink component carrier can include downlink HARQ information,CSI, SR information, and RACH signaling.

At 660, base station 105 may optionally reconfigure UE 115 with adifferent primary uplink component carrier at a later time. For example,base station 105 may receive an indication from UE 115 of a preferencefor a different primary uplink component carrier (e.g., based on changesin communication parameters such as a changing in loading for differentuplink component carriers). If the preferred primary uplink componentcarrier is appropriate (e.g., not overloaded), base station 105, and mayreconfigure the UE 115 to use that preferred primary uplink componentcarrier. In some implementations, base station 105 may reconfigure UE115 to use a different primary uplink component carrier without anindication for UE preference; for example, in order to balance loadsamong a carriers.

It should be noted that these methods describe possible implementation,and that the operations and the steps may be rearranged or otherwisemodified such that other implementations are possible. In some examples,aspects from two or more of the methods may be combined. For example,aspects of each of the methods may include steps or aspects of the othermethods, or other steps or techniques described herein.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notto be limited to the examples and designs described herein but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described above can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different (physical)locations. Also, as used herein, including in the claims, “or” as usedin a list of items (for example, a list of items prefaced by a phrasesuch as “at least one of” or “one or more”) indicates an inclusive listsuch that, for example, a list of at least one of A, B, or C means A orB or C or AB or AC or BC or ABC (i.e., A and B and C).

Computer-readable media includes both computer storage media andcommunication media including any medium that facilitates transfer of acomputer program from one place to another. A computer storage mediummay be any available medium that can be accessed by a general purpose orspecial purpose computer but the phrase “computer storage medium” doesnot refer to a transitory propagating signal. By way of example, and notlimitation, computer storage media can comprise RAM, ROM, electricallyerasable programmable read only memory (EEPROM), compact disk (CD) ROMor other optical disk storage, magnetic disk storage or other magneticstorage devices, or other medium that can be used to store desiredprogram code means in the form of instructions or data structures andthat can be accessed by a general-purpose or special-purpose computer,or a general-purpose or special-purpose processor. Also, a connectionthat transmits information is referred to as a communication medium. Forexample, if the software is transmitted from a website, server, or otherremote source using a coaxial cable, fiber optic cable, twisted pair,digital subscriber line (DSL), or wireless technologies such asinfrared, radio, and microwave, then the coaxial cable, fiber opticcable, twisted pair, DSL, or wireless technologies such as infrared,radio, and microwave are included in the definition of communicationmedium.

The techniques herein are described with reference to systems that usewide bands, such as 5G or new radio (NR) systems and future systems thatuse spectrum in the mmW range of the electromagnetic spectrum. Ifapplicable, techniques described herein may be used for various wirelesscommunications systems such as CDMA, TDMA, FDMA, OFDMA, single carrierfrequency division multiple access (SC-FDMA), and other systems. Theterms “system” and “network” are often used interchangeably. A CDMAsystem may implement a radio technology such as CDMA2000, UniversalTerrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000, IS-95,and IS-856 standards. IS-2000 Releases 0 and A are commonly referred toas CDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as (Global System for Mobilecommunications (GSM)). An OFDMA system may implement a radio technologysuch as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE802.11, IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, etc. UTRA andE-UTRA are part of Universal Mobile Telecommunications system (UniversalMobile Telecommunications System (UMTS)). 3GPP LTE and LTE-advanced(LTE-A) are new releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS,LTE, LTE-a, and GSM are described in documents from an organizationnamed “3rd Generation Partnership Project” (3GPP). CDMA2000 and UMB aredescribed in documents from an organization named “3rd GenerationPartnership Project 2” (3GPP2). The techniques described herein may beused for the systems and radio technologies mentioned above as well asother systems and radio technologies. The description herein, however,describes a 5G system for purposes of example, and 5G terminology isused in much of the description above, although the techniques areapplicable beyond 5G applications.

Base stations may include or may be referred to by those skilled in theart as a base transceiver station, a radio base station, an access point(AP), a radio transceiver, a NodeB, eNodeB (eNB), Home NodeB, a HomeeNodeB, gNodeB, or some other suitable terminology. The geographiccoverage area for a base station may be divided into sectors making uponly a portion of the coverage area. The wireless communications systemor systems described herein may include base stations of different types(e.g., macro or small cell base stations). The UEs described herein maybe able to communicate with various types of base stations and networkequipment including macro eNBs, small cell eNBs, relay base stations,and the like. There may be overlapping geographic coverage areas fordifferent technologies. In some cases, different coverage areas may beassociated with different communication technologies. In some cases, thecoverage area for one communication technology may overlap with thecoverage area associated with another technology. Different technologiesmay be associated with the same base station, or with different basestations.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell is alower-powered base station, as compared with a macro cell, that mayoperate in the same or different (e.g., licensed, unlicensed, etc.)frequency bands as macro cells. Small cells may include pico cells,femto cells, and micro cells according to various examples. A pico cell,for example, may cover a small geographic area and may allowunrestricted access by UEs with service subscriptions with the networkprovider. A femto cell may also cover a small geographic area (e.g., ahome) and may provide restricted access by UEs having an associationwith the femto cell (e.g., UEs in a closed subscriber group (CSG), UEsfor users in the home, and the like). An eNB for a macro cell may bereferred to as a macro eNB. An eNB for a small cell may be referred toas a small cell eNB, a pico eNB, a femto eNB, or a home eNB. An eNB maysupport one or multiple (e.g., two, three, four, and the like) cells(e.g., component carriers (CCs)). A UE may be able to communicate withvarious types of base stations and network equipment including macroeNBs, small cell eNBs, relay base stations, and the like.

The wireless communications system or systems described herein maysupport synchronous or asynchronous operation. For synchronousoperation, the base stations may have similar frame timing, andtransmissions from different base stations may be approximately alignedin time. For asynchronous operation, the base stations may havedifferent frame timing, and transmissions from different base stationsmay not be aligned in time. The techniques described herein may be usedfor either synchronous or asynchronous operations.

The DL transmissions described herein may also be called forward linktransmissions while the UL transmissions may also be called reverse linktransmissions. Each communication link described herein including, forexample, wireless communications system 100 of FIG. 1 may include one ormore carriers, where each carrier may be a signal made up of multiplesub-carriers (e.g., waveform signals of different frequencies). Eachmodulated signal may be sent on a different sub-carrier and may carrycontrol information (e.g., reference signals, control channels, etc.),overhead information, user data, etc. The communication links describedherein (e.g., communication links of FIG. 1) may transmit bidirectionalcommunications using frequency division duplex (FDD) (e.g., using pairedspectrum resources) or time division duplex (TDD) operation (e.g., usingunpaired spectrum resources). Frame structures may be defined for FDD(e.g., frame structure type 1) and TDD (e.g., frame structure type 2).

Thus, aspects of the disclosure may provide for carrier aggregationsignaling. It should be noted that these methods describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified such that other implementations are possible. Insome examples, aspects from two or more of the methods may be combined.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a digital signal processor (DSP), an ASIC, afield programmable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described herein.A general-purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration). Thus, the functions described herein may be performed byone or more other processing units (or cores), on at least oneintegrated circuit (IC). In various examples, different types of ICs maybe used (e.g., Structured/Platform ASICs, an FPGA, or anothersemi-custom IC), which may be programmed in any manner known in the art.The functions of each unit may also be implemented, in whole or in part,with instructions embodied in a memory, formatted to be executed by oneor more general or application-specific processors.

In the appended figures, similar components or features may have thesame or similar reference label. Further, various components of the sametype may be distinguished by following the reference label by a dash anda second label that distinguishes among the similar components. If justthe first reference label is used in the specification, the descriptionis applicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

What is claimed is:
 1. A method of wireless communication performed by auser equipment (UE) in communication with a base station, the methodcomprising: receiving information indicative of a plurality of candidateuplink component carriers in the non-mmW (millimeter wave) spectrum,each of the plurality of candidate uplink component carriers availableto be associated with a particular downlink component carrier in the mmWspectrum; in response to receiving the information indicative of theplurality of candidate uplink component carriers, selecting at least aprimary uplink component carrier from the plurality of candidate uplinkcomponent carriers; and transmitting a signal to the base station usingthe primary uplink component carrier.
 2. The method of claim 1, whereinreceiving information indicative of a plurality of candidate uplinkcomponent carriers in the non-mmW spectrum comprises receiving at leastfrequency information and one or more random access channel (RACH)parameters for each of the candidate uplink component carriers.
 3. Themethod of claim 1, wherein selecting at least a primary uplink componentcarrier from the plurality of candidate uplink component carrierscomprises determining that a set S of candidate uplink componentcarriers supported by the UE from the total T candidate uplink componentcarriers are supported by the UE.
 4. The method of claim 3, wherein S isgreater than one, and further comprising selecting the primary uplinkcomponent carrier from the S supported candidate uplink componentcarriers based on one or more uplink communication parameters.
 5. Themethod of claim 4, wherein the one or more uplink communicationparameters include at least one parameter selected from the groupconsisting of UE compatibility with each of the candidate uplinkcomponent carriers, a current load level of each of the S supportedcandidate uplink component carriers, an expected load level of each ofthe S supported candidate uplink component carriers, and an incumbentpriority for each of the S supported candidate uplink componentcarriers.
 6. The method of claim 1, further comprising selecting atleast one secondary uplink component carrier from the candidate uplinkcomponent carriers.
 7. The method of claim 1, wherein transmitting thesignal to the base station using the primary uplink component carriercomprises comprising transmitting a UE capability report to the basestation using the primary uplink component carrier, the UE capabilityreport including UE uplink carrier capability information.
 8. The methodof claim 7, further comprising receiving a configuration of one or moresecondary uplink component carriers associated with the particulardownlink component carrier after transmitting the UE capability reportto the base station.
 9. The method of claim 8, further comprisingtransmitting control signaling and data to the base station using theprimary uplink component carrier and transmitting data to the basestation using the one or more secondary uplink component carriers. 10.The method of claim 7, further comprising receiving a configuration ofan updated primary uplink component carrier.
 11. The method of claim 10,further comprising, transmitting control information to the base stationusing the updated primary uplink component carrier subsequent toreceiving the configuration of the updated primary uplink componentcarrier.
 12. The method of claim 1, further comprising transmitting anindication to indicate a preferred uplink component carrier to use asthe primary uplink component carrier.
 13. A method of wirelesscommunication performed by a user equipment (UE) in communication with abase station, the method comprising: receiving information indicative ofan initial configured primary uplink component carrier from the basestation, wherein the initial configured primary uplink component carrieris a non-mmW carrier paired with a particular downlink mmW carrier;transmitting a UE capability report to the base station using theinitial configured primary uplink component carrier, wherein the UEcapability report includes UE uplink carrier capability information; andreceiving a configuration of one or more secondary uplink componentcarriers associated with the particular downlink mmW carrier from thebase station in response to the UE capability report.
 14. The method ofclaim 13, further comprising: transmitting control signaling and data tothe base station using the primary uplink component carrier andtransmitting data to the base station using the one or more secondaryuplink component carriers.
 15. The method of claim 14, wherein thecontrol signaling comprises information having at least one informationtype selected from the group consisting of downlink hybrid automaticrepeat request (HARQ) information, channel state information (CSI),scheduling request (SR) information, and random access channel (RACH)information.
 16. The method of claim 14, further comprising receiving aconfiguration of an updated primary uplink component carrier from thebase station at a later time.
 17. The method of claim 16, furthercomprising, transmitting control information to the base station usingthe updated primary uplink component carrier subsequent to receiving theconfiguration of the updated primary uplink component carrier.
 18. Themethod of claim 13, further comprising transmitting an indication toindicate a preferred uplink component carrier to use as the primaryuplink component carrier.
 19. A user equipment (UE) for wirelesscommunication comprising: means for receiving information indicative ofa plurality of candidate uplink component carriers in the non-mmWspectrum, each of the plurality of candidate uplink component carriersavailable to be associated with a particular downlink component carrierin the mmW spectrum; means for selecting at least a primary uplinkcomponent carrier from the plurality of candidate uplink componentcarriers in response to receiving the information indicative of theplurality of candidate uplink component carriers; and means fortransmitting a signal to a base station using the primary uplinkcomponent carrier.
 20. The user equipment of claim 19, wherein the meansfor receiving information indicative of a plurality of candidate uplinkcomponent carriers in the non-mmW spectrum comprises means for receivingat least frequency information and one or more random access channel(RACH) parameters for each of the candidate uplink component carriers.21. The user equipment of claim 19, wherein the means for selecting atleast a primary uplink component carrier from the plurality of candidateuplink component carriers comprises means for determining that a set Sof candidate uplink component carriers supported by the UE from thetotal T candidate uplink component carriers are supported by the UE. 22.The user equipment of claim 21, wherein S is greater than one, andfurther comprising means for selecting the primary uplink componentcarrier from the S supported candidate uplink component carriers basedon one or more uplink communication parameters.
 23. The user equipmentof claim 22, wherein the one or more uplink communication parametersinclude at least one parameter selected from the group consisting of UEcompatibility with each of the candidate uplink component carriers, acurrent load level of each of the S supported candidate uplink componentcarriers, an expected load level of each of the S supported candidateuplink component carriers, and an incumbent priority for each of the Ssupported candidate uplink component carriers.
 24. The user equipment ofclaim 19, further comprising means for selecting at least one secondaryuplink component carrier from the candidate uplink component carriers.25. A user equipment (UE) for wireless communication comprising: meansfor receiving information indicative of an initial configured primaryuplink component carrier from a base station, wherein the initialconfigured primary uplink component carrier is a non-mmW carrier pairedwith a particular downlink mmW carrier; means for transmitting a UEcapability report to the base station using the initial configuredprimary uplink component carrier, wherein the UE capability reportincludes UE uplink carrier capability information; and means forreceiving a configuration of one or more secondary uplink componentcarriers associated with the particular downlink mmW carrier from thebase station in response to the UE capability report.
 26. The userequipment of claim 25, further comprising: means for transmittingcontrol signaling and data to the base station using the primary uplinkcomponent carrier and transmitting data to the base station using theone or more secondary uplink component carriers.
 27. The user equipmentof claim 26, wherein the control signaling comprises information havingat least one information type selected from the group consisting ofdownlink hybrid automatic repeat request (HARQ) information, channelstate information (CSI), scheduling request (SR) information, and randomaccess channel (RACH) information.
 28. The user equipment of claim 25,further comprising means for receiving a configuration of an updatedprimary uplink component carrier from the base station after receivingthe configuration of the initial configured primary uplink componentcarrier.
 29. The user equipment of claim 28, further comprising, meansfor transmitting control information to the base station using theupdated primary uplink component carrier subsequent to receiving theconfiguration of the updated primary uplink component carrier.
 30. Theuser equipment of claim 25, further comprising means for transmitting anindication to indicate a preferred uplink component carrier to use asthe primary uplink component carrier.
 31. A user equipment (UE)comprising: receive circuitry configured to receive mmW signals on oneor more downlink mmW carriers; memory circuitry configured to storereceived information indicative of a plurality of candidate uplinkcomponent carriers in the non-mmW spectrum, each of the plurality ofcandidate uplink component carriers available to be associated with aparticular downlink component carrier; processor circuitry configured toaccess the information indicative of the plurality of candidate uplinkcomponent carriers and to select at least a primary uplink componentcarrier; and transmit circuitry configured to transmit a signal to abase station using the primary uplink component carrier.
 32. The userequipment of claim 31, wherein the information indicative of a pluralityof candidate uplink component carriers in the non-mmW spectrum comprisesat least frequency information and one or more random access channel(RACH) parameters for each of the candidate uplink component carriers.33. The user equipment of claim 31, wherein the processor circuitry isconfigured to select the at least a primary uplink component carrierfrom the plurality of candidate uplink component carriers from a set Sof candidate uplink component carriers supported by the UE from a totalT candidate uplink component carriers are supported by the UE.
 34. Theuser equipment of claim 33, wherein S is greater than one, and whereinthe processor circuitry is configured to select the primary uplinkcomponent carrier from the S supported candidate uplink componentcarriers based on one or more uplink communication parameters.
 35. Theuser equipment of claim 34, wherein the one or more uplink communicationparameters include at least one parameter selected from the groupconsisting of UE compatibility with each of the candidate uplinkcomponent carriers, a current load level of each of the S supportedcandidate uplink component carriers, an expected load level of each ofthe S supported candidate uplink component carriers, and an incumbentpriority for each of the S supported candidate uplink componentcarriers.
 36. The user equipment of claim 31, wherein the processorcircuitry is further configured to select at least one secondary uplinkcomponent carrier from the candidate uplink component carriers.
 37. Theuser equipment of claim 31, wherein the processor circuitry is furtherconfigured to generate a message to be transmitted to the base station,the message comprising a UE capability report including UE uplinkcarrier capability information.
 38. A user equipment (UE) for wirelesscommunication comprising: memory circuitry to store received informationindicative of an initial configured primary uplink component carrierfrom a base station, wherein the initial configured primary uplinkcomponent carrier is a non-mmW carrier paired with a particular downlinkmmW carrier, the memory circuitry further to store receivedconfiguration information of one or more secondary uplink componentcarriers associated with the particular downlink mmW carrier; processorcircuitry configured to generate a UE capability report to transmit tothe base station using the initial configured primary uplink componentcarrier, wherein the UE capability report includes UE uplink carriercapability information; and transmit circuitry to transmit the UEcapability report to the base station.
 39. The user equipment of claim38, wherein the receive circuitry is configured to receive aconfiguration of an updated primary uplink component carrier from thebase station at a later time, and wherein the processor circuitry isfurther configured to generate control signaling to transmit to the basestation using the initial configured primary uplink component carrierprior to the later time and the updated primary uplink component carrierafter the later time.
 40. The user equipment of claim 39, wherein thecontrol signaling comprises information having at least one informationtype selected from the group consisting of downlink hybrid automaticrepeat request (HARQ) information, channel state information (CSI),scheduling request (SR) information, and random access channel (RACH)information.
 41. A method of wireless communication performed by a basestation in communication with a user equipment (UE) comprising:transmitting to the UE information indicative of a plurality ofcandidate non-mmW uplink component carriers to be paired with aparticular downlink mmW component carrier; receiving an indication of apreferred uplink component carrier of the plurality of candidate uplinkcomponent carrier from the UE; selecting the preferred uplink componentcarrier or a different uplink component carrier as an initial primaryuplink component carrier for the UE; and configuring the UE with theinitial primary uplink component carrier.
 42. The method of claim 41,wherein the information indicative of the plurality of candidate uplinkcomponent carriers comprises frequency information and one or morerandom access channel (RACH) parameters for each of the candidate uplinkcomponent carriers.
 43. The method of claim 41, wherein selecting thepreferred uplink component carrier or a different uplink componentcarrier as an initial primary uplink component carrier comprisesselecting a different uplink component carrier as an initial primaryuplink component carrier based on relative loading of the differentuplink component carrier and the preferred uplink component carrier. 44.The method of claim 41, further comprising receiving a UE capabilityreport including UE uplink carrier capability information andconfiguring the UE with at least one secondary uplink component carrierbased on the UE uplink carrier capability information.
 45. The method ofclaim 41, further comprising, subsequent to configuring the UE with theinitial primary uplink component carrier, configuring the UE with anupdated primary uplink component carrier.
 46. A base station forwireless communication comprising: means for transmitting to the UEinformation indicative of a plurality of candidate non-mmW uplinkcomponent carriers to be paired with a particular downlink mmW componentcarrier; means for receiving an indication of a preferred uplinkcomponent carrier of the plurality of candidate uplink component carrierfrom the UE; means for selecting the preferred uplink component carrieror a different uplink component carrier as an initial primary uplinkcomponent carrier for the UE; and means for configuring the UE with theinitial primary uplink component carrier.
 47. The base station of claim46, wherein the information indicative of the plurality of candidateuplink component carriers comprises frequency information and one ormore random access channel (RACH) parameters for each of the candidateuplink component carriers.
 48. The base station of claim 46, wherein themeans for selecting the preferred uplink component carrier or adifferent uplink component carrier as an initial primary uplinkcomponent carrier comprises means for selecting a different uplinkcomponent carrier as an initial primary uplink component carrier basedon relative loading of the different uplink component carrier and thepreferred uplink component carrier.
 49. The base station of claim 46,further comprising means for receiving a UE capability report includingUE uplink carrier capability information and configuring the UE with atleast one secondary uplink component carrier based on the UE uplinkcarrier capability information.
 50. The base station of claim 46,further comprising means for configuring the UE with an updated primaryuplink component carrier subsequent to configuring the UE with theinitial primary uplink component carrier.